PSEUDOCAPACITIVE MECHANISM OF FLEXIBLE MNO2 ELECTRODES IN NOVEL ROOM TEMPERATURE MOLTEN SALTS ELECTROLYTES INVESTIGATED USING IN-SITU X-RAY ABSORPTION SPECTRA

PSEUDOCAPACITIVE MECHANISM OF FLEXIBLE MNO2 ELECTRODES IN NOVEL ROOM TEMPERATURE MOLTEN SALTS ELECTROLYTES INVESTIGATED USING IN-SITU X-RAY ABSORPTION SPECTRA

MnO2 nanowires were grown on flexible carbon-fiber paper electrodes according to a simple synthesis. The pseudocapacitivebehavior of MnO2 nanowire was tested in various electrolytes. It was found that urea-LiPF6 room temperature molten salts (RTMS)was the most effective electrolyte to conduct electricity. The ideal MnO2 supercapacitor electrode, 200 F g-1 at 5 mV s-1, wasidentified. This supercapacitor could perform a wide potential window of 3 V. The energy storage mechanism was graphed inin-situ X-ray absorption spectroscopy (XAS). The urea-LiPF6 RTMS was proved to provide the functioning ions that stabilize thevariation of the Mn valence state during the charging and discharging of RTMS electrolytes. These complementary results couldprovide scalable and inexpensive applications of high performance reduction/oxidation metal oxide energy storage systems.